Difference between split ,splitby and split1R used in sort

There are many different ways to split a datasets into different datasets.

Split, Splitby and Split1R are two of the ways to split a dataset a jcl.

The below jcl and the result will be able to make us understand the difference between split ,splitby and Split1R.

Usage of Split:

Split is going to get the even records in one dataset and the odd records in another i.e. first line copied to first dataset, 2nd line copied to second dataset, then 3rd line copied to third dataset and so on..

JCL for Split:

//NUMHP53A JOB ,'SPLIT',MSGCLASS=Q,MSGLEVEL=(1,1),NOTIFY=&SYSUID     //STEP01         EXEC PGM=SORT                                             //SORTIN        DD DSN=NUMHP53.MAITREE.DATA9,                             //                      DISP=SHR                                                //SORTOUT1 DD DSN=NUMHP53.MAITREE.DATA91,                            //                      DISP=(MOD,CATLG,DELETE),                                  //                      UNIT=SYSDA,SPACE=(TRK,(1,1),RLSE),                        //                      DCB=(*.SORTIN)                                            //SORTOUT2 DD DSN=NUMHP53.MAITREE.DATA92,                            //                      DISP=(MOD,CATLG,DELETE),                                  //                      UNIT=SYSDA,SPACE=(TRK,(1,1),RLSE),                         //                      DCB=(*.SORTIN)                                            //SYSOUT      DD SYSOUT=*                                               //SYSIN          DD *                                                                             OPTION COPY                                                                             OUTFILE FNAMES=(SORTOUT1,SORTOUT2),SPLIT                        /*  //*

Input dataset:

VIEW       NUMHP53.MAITREE.DATA9                           Columns 00001 00072 Command ===>                                                  Scroll ===> CSR  ****** ***************************** Top of Data ****************************** 000001 This is the 1st   line                                                  000002 This is the 2nd   line                                                  000003 This is the 3rd   line                                                  000004 This is the 4th   line                                                  000005 This is the 5th   line                                                  000006 This is the 6th   line                                                  000007 This is the 7th   line                                                  000008 This is the 8th   line                                                  000009 This is the 9th   line                                                  000010 This is the 10th  line                                                  000011 This is the 11th  line                                                  ****** **************************** Bottom of Data ****************************

Output Datasets:

VIEW       NUMHP53.MAITREE.DATA91                          Columns 00001 00072 Command ===>                                                  Scroll ===> CSR  ****** ***************************** Top of Data ****************************** 000001 This is the 1st   line                                                  000002 This is the 3rd   line                                                  000003 This is the 5th   line                                                   000004 This is the 7th   line                                                  000005 This is the 9th   line                                                  000006 This is the 11th  line                                                   ****** **************************** Bottom of Data ****************************                                                                                VIEW       NUMHP53.MAITREE.DATA92                          Columns 00001 00072 Command ===>                                                  Scroll ===> CSR  ****** ***************************** Top of Data ****************************** 000001 This is the 2nd   line                                                  000002 This is the 4th   line                                                  000003 This is the 6th   line                                                  000004 This is the 8th   line                                                  000005 This is the 10th  line                                                   ****** **************************** Bottom of Data ****************************

Usage of Splitby:

Splitby splits the input dataset by the number we want it to. 

In the below example I have used a single dataset to be splited by 4.

The first four records are copied into 1st dataset, fifth to eighth record are copied to 2nd dataset, then again the ninth to eleventh records are copied into the 1st dataset. 

JCL for Splitby:

//NUMHP53A JOB ,'SPLIT',MSGCLASS=Q,MSGLEVEL=(1,1),NOTIFY=&SYSUID   //STEP01   EXEC PGM=SORT                                           //SORTIN   DD DSN=NUMHP53.MAITREE.DATA9,                           //            DISP=SHR                                             //SORTOUT1 DD DSN=NUMHP53.MAITREE.DATA91,                          //         DISP=(NEW,CATLG,DELETE),                                 //         UNIT=SYSDA,SPACE=(TRK,(1,1),RLSE),                      //         DCB=(*.SORTIN)                                          //SORTOUT2 DD DSN=NUMHP53.MAITREE.DATA92,                          //         DISP=(NEW,CATLG,DELETE),                                 //         UNIT=SYSDA,SPACE=(TRK,(1,1),RLSE),                      //         DCB=(*.SORTIN)                                          //SYSOUT   DD SYSOUT=*                                             //SYSIN    DD *                                                         OPTION COPY                                                        OUTFILE FNAMES=(SORTOUT1,SORTOUT2),SPLITBY=4                  /*                                                                  //*

Input dataset:

VIEW       NUMHP53.MAITREE.DATA9                           Columns 00001 00072 Command ===>                                                  Scroll ===> CSR  ****** ***************************** Top of Data ****************************** 000001 This is the 1st   line                                                  000002 This is the 2nd   line                                                  000003 This is the 3rd   line                                                  000004 This is the 4th   line                                                  000005 This is the 5th   line                                                  000006 This is the 6th   line                                                  000007 This is the 7th   line                                                  000008 This is the 8th   line                                                  000009 This is the 9th   line                                                  000010 This is the 10th  line                                                  000011 This is the 11th  line                                                  ****** **************************** Bottom of Data ****************************

Output dataset:

VIEW       NUMHP53.MAITREE.DATA91                          Columns 00001 00072 Command ===>                                                  Scroll ===> CSR  ****** ***************************** Top of Data ****************************** 000001 This is the 1st   line                                                  000002 This is the 2nd   line                                                  000003 This is the 3rd   line                                                  000004 This is the 4th   line                                                  000005 This is the 9th   line                                                  000006 This is the 10th  line                                                  000007 This is the 11th  line                                                  ****** **************************** Bottom of Data ****************************

VIEW       NUMHP53.MAITREE.DATA92                          Columns 00001 00072 Command ===>                                                  Scroll ===> CSR  ****** ***************************** Top of Data ****************************** 000001 This is the 5th   line                                                  000002 This is the 6th   line                                                   000003 This is the 7th   line                                                  000004 This is the 8th   line                                                  ****** **************************** Bottom of Data ****************************

Usage of SPLIT1R:

SPLIT1R should be the safest way to split a dataset into number of datasets as it does not carry out the rotation. 

In the below example, I have used SPLIT1R=4 and as a result, the first 4 records are copied to 1st dataset and the remaining records are copied into the second dataset. 

JCL for SPLIT1R:

//NUMHP53A JOB ,'SPLIT',MSGCLASS=Q,MSGLEVEL=(1,1),NOTIFY=&SYSUID  //STEP01        EXEC PGM=SORT                                          //SORTIN       DD DSN=NUMHP53.MAITREE.DATA9,                          //                    DISP=SHR                                             //SORTOUT1 DD DSN=NUMHP53.MAITREE.DATA91,                         //                   DISP=(NEW,CATLG,DELETE),                               //                   UNIT=SYSDA,SPACE=(TRK,(1,1),RLSE),                     //                   DCB=(*.SORTIN)                                         //SORTOUT2 DD DSN=NUMHP53.MAITREE.DATA92,                         //                   DISP=(NEW,CATLG,DELETE),                               //                   UNIT=SYSDA,SPACE=(TRK,(1,1),RLSE),                      //                   DCB=(*.SORTIN)                                         //SYSOUT     DD SYSOUT=*                                            //SYSIN        DD *                                                        OPTION COPY                                                        OUTFILE FNAMES=(SORTOUT1,SORTOUT2),SPLIT1R=4                 /*                                                                //*

Input dataset:

VIEW       NUMHP53.MAITREE.DATA9                           Columns 00001 00072 Command ===>                                                  Scroll ===> CSR  ****** ***************************** Top of Data ****************************** 000001 This is the 1st   line                                                  000002 This is the 2nd   line                                                  000003 This is the 3rd   line                                                  000004 This is the 4th   line                                                  000005 This is the 5th   line                                                  000006 This is the 6th   line                                                  000007 This is the 7th   line                                                  000008 This is the 8th   line                                                  000009 This is the 9th   line                                                  000010 This is the 10th  line                                                  000011 This is the 11th  line                                                  ****** **************************** Bottom of Data ****************************

Output Datasets:

VIEW       NUMHP53.MAITREE.DATA91                          Columns 00001 00072 Command ===>                                                  Scroll ===> CSR  ****** ***************************** Top of Data ****************************** 000001 This is the 1st   line                                                  000002 This is the 2nd   line                                                   000003 This is the 3rd   line                                                  000004 This is the 4th   line                                                  ****** **************************** Bottom of Data ****************************

VIEW       NUMHP53.MAITREE.DATA92                          Columns 00001 00072 Command ===>                                                  Scroll ===> CSR  ****** ***************************** Top of Data ****************************** 000001 This is the 5th   line                                                  000002 This is the 6th   line                                                   000003 This is the 7th   line                                                  000004 This is the 8th   line                                                  000005 This is the 9th   line                                                  000006 This is the 10th  line                                                  000007 This is the 11th  line                                                  ****** **************************** Bottom of Data ****************************